A young man worked very hard on his lessons. He was too busy to have a rest. One day he found that he couldn't fall asleep at night. As he became ill, he couldn't go to sleep. When he went to bed, he closed his eyes and tried to sleep. But he always failed.
After a few days he decided to see a doctor.
"I just can't go to sleep at night. What should I do?" he asked.
"I have a suggestion," said the doctor. "You can try to count numbers. When you count to one thousand, you will be asleep. I am sure of it. "
The next day the man returned to the doctor's office.
"Well," said the doctor. "How are you today? Did you try my suggestion?"
The man still looked tired. "Yes," he said. "I tried to count one, two, three.. , up to one thousand. But when I counted to five hundred and sixty--nine, I began to feel sleepy. I had to get up and drink some tea so that I could go on counting up to one thousand. But then I still couldn't fall asleep. "
【小题1】Why couldn't the young man go to sleep at night?

A young man worked very hard at his lessons. He was too busy to have a rest. At last, he became ill, so he couldn’t go to sleep. Every night, when he went to bed, he closed his eyes and tried to sleep. But he always stayed awake and couldn’t fall asleep.
After some days, he decided to see a doctor.“I just can’t go to sleep at night. What should I do? Could you please help me?”
“I have a suggestion(建议)，”said the doctor. “Try counting numbers. By the time you reach one thousand, you’ll be asleep. I’m sure of it.”
The next day the man returned to the doctor’s office. “Well,” said the doctor, how are you today? Did you try my suggestion?”
The man still looked tired. “Yes,” he said, “I tried counting one , two, three—up to one thousand. But when I reached five hundred and sixty-nine, I began to feel sleepy. I had to get up and drink some tea so that I could go on counting up to one thousand. But then I still couldn’t fall asleep.”
【小题1】The young man couldn’t go to sleep because                       。

A young man worked very hard at his lessons. He was too busy to have a rest. At last, he became ill, so he couldn’t go to sleep. Every night, when he went to bed, he closed his eyes and tried to sleep. But he always stayed awake and couldn’t fall asleep.
After some days, he decided to see a doctor. “I just can’t go to sleep at night. What should I do? Could you please help me?”
“I have a suggestion(建议)，”said the doctor. “Try counting numbers. By the time you reach one thousand, you’ll be asleep. I’m sure of it.”
The next day the man returned to the doctor’s office. “Well,” said the doctor, how are you today? Did you try my suggestion?”
The man still looked tired. “Yes,” he said, “I tried counting one, two, and three— up to one thousand. But when I reached five hundred and sixty-nine, I began to feel sleepy. I had to get up and drink some tea so that I could go on counting up to one thousand. But then I still couldn’t fall asleep.”
【小题1】The young man couldn’t go to sleep because ____________________,